The present invention relates to wide-body aircraft such as the Boeing 747 and the like and, more particularly, relates to the improved utilization of interior space in such aircraft so that the aircraft is able to greatly increase its passenger and/or cargo carrying capacity.
It is well known in the airline industry that airline profitability is directly related to passenger revenues and cargo revenues which are, in turn, a function of passenger seating space and cargo carrying space, respectively. The greater the passenger seating space, the greater are the potential passenger revenues. Similarly, the greater the cargo carrying space, the greater are the potential cargo revenues.
It follows then that a way to increase profitability is to increase passenger seating space and cargo carrying space.
The present invention is based upon the realization that the wide-body aircraft of today are not configured for the best use of the available space within the confines of the aircraft. Since wide-body aircraft (both passenger carrying and cargo carrying) bulk-out rather than weight-out (i.e., the lifting capacity of the aircraft is not the limiting factor), the entire economics of the aircraft revolves around the efficient use of the available space within the aircraft. This reasoning will usually not apply on the longest routes since the consumption of fuel will then become a problem.
A great deal of effort has been expended to identify and optimize the overall performance of the aircraft. This includes work on increased engine performance, wing efficiency, laminar flow and other items which dictate the basic performance variables of the aircraft, such as cost per mile.
On the other hand, the efficient use of the interior capacity of the aircraft has, for the most part, been overlooked by airframe designers. It is believed that the maximum lift capacity of the aircraft is rarely utilized because of this inefficient use of the interior capacity of the aircraft.
On wide-body aircraft there is typically a main deck. The main deck may be used for carrying passengers or cargo with the space below the main deck used exclusively for carrying cargo. At various times the aircraft may fly only passengers and their baggage, only cargo, or a combination of passengers and cargo. In any case, the configuration of wide-body aircraft is such that only cargo is carried below the main deck, due at least in part to the fact that there is insufficient headroom between the main deck and the bottom of the aircraft to accommodate passengers.
It is well known that there is a plenum or airspace above the ceiling of the passenger compartment. This plenum is typically used for auxiliary equipment, control cables, wiring, plumbing and the like. There is, however, excess capacity in the plenum such that this volume of the interior of the aircraft is sorely under utilized. This is most clearly the case with the Boeing 747 but, to a somewhat lesser degree, is also the case with the other wide-body aircraft such as the McDonnell-Douglas DC10, the Airbus A300 and the Lockheed L1011. The Boeing 747, for example, has about 12 feet of space above the main deck, only about 8 feet of which is necessary for the main deck headroom and the plenum. The remainder is wasted space.
The under utilization of the interior of the aircraft and the plenum has been, at least partially, recognized in Greiss U.S. Pat. No. 4,055,317, the disclosure of which is incorporated by reference herein, wherein an aft galley is configured so as to protrude into the plenum. That is, the floor of the galley is raised above the main passenger deck so that the ceiling of the galley extends well into the plenum. There is now room between the main deck and the raised galley floor for the storage of food and other items. In this patent, there is no suggestion that the passenger compartment itself could be altered to improve the utilization of space.
Australian Patent No. 164626, the disclosure of which is incorporated by reference herein, illustrates a double-decked configuration in a portion of an aircraft which is suitable for carrying two levels of passengers or cargo. It is to be noted that in the passenger configuration the seats must be staggered so as to provide adequate passenger headroom.
It must be appreciated by now that an object of the invention is to provide a wide-body aircraft which is suitable for increasing passenger and cargo revenues.
It is another object of the invention to provide a wide-body aircraft configuration in which there is greatly improved utilization of the interior space of the aircraft.
It is yet another object of the invention to provide a wide-body aircraft configuration providing increased passenger seating space and increased cargo carrying space without unduly increasing the exterior dimensions of the aircraft.
These and other objects of the invention will become more apparent after referring to the following description of the invention in conjunction with the accompanying drawings.